Worm-gear axle



June 3, 1930. R. v. HurcHl'NsoN 1,761,922

woRM GEAR AXL Filed April 2v, 1929.

In/vented:

Tatented June 3, 1930 ROLAND v. HUTCHINSON, F LANSING, CORPORATION, OF DETROIT,

LICHIGAN, ASSIGNOR TO GENERAL MOTORS MICHIGAN, A CORPORATION OF DELAWARE WORM-GEAR AXLE Appiiation mea April 27,

This invention relates to automotive vehicles and has particular reference to improvements in structural details at the rear axle where the propeller shaft joinsfonto the differential.

The improvements relate to worm driven rear axles having an underslung usually inl clined propeller shaft. 1n the past it has been customary toprovide the rear or lowerm most end ofthe propeller shaft or worm which drives the differential with a thrust bearing which extended rearwardly of and below the axle housing and decreased the ground; clearance. ln the present invention is the thrust bearing is placed at the front, leaving but the ordinary radial bearing at the rear. Because of the fact that the drive.

axle is inclined, the placing of the thrust hearin at the front end will increase the 2o groun the effective operation of the drive.

novel oil seal is also placed at the front end of the thrust bearing. This novel oil seal comprises a washer secured.to the propeller shaft and having an outer spherical formation-or seat. yOn. .this seat -there is tted the corresponding spherical seat of a spherical sealing ring preferably made of brass or durex. To the ring there is secured se one end of a bellows the opposite end of l which Ais secured to a retainer for the'thrust bearing. Thel bellows presses or urges the ring against the seat of the washer to maintain an oil tight or non-leak proof connection at all times. The spherical portions of the washer and ringl are preferably formed or generated from a center which coincides atthe center of zero bending of the forward portion of the wormshafti,

A further-feature of the invention is in Y providingthe usual differential carrier of the conventional. differential Jwith a number lof interrupted splines and mounting on a stud at each interru ted portion one' of the usual' differential pinlons. The object of this construction is to obtain a reduction in diameter* of the gears and hence a closer center or reduced center distance.

y Asa modification of the invention instead ofthe bellows used on the oilseal it is within clearance Without interfering with f 1929. Serial No. 358,585.

the scope of the invention to use a flanged washer which seats on the ring and is pressed l against the spherical seat by means of a coil spring.

As a further modification of the invention use may be made of a packing held between a suitable gland and a retainer around one of the sleeved ends of the universal joint. By forcing the retaining member and gland togetheran oil tight seal is obtained.

Un the drawing:

Fig. l shows a transverse sectional view through the differential and driving gearingr of the rear axle of an automotive vehicle, showing the inclined propeller shaft worm.

Fig. 2 is a section on the line 2--2 of Fig. 1.

Fig. 3 is a-modiiication of the oil seal shown in Fig. 1.

Blig. 4 is a further modification of the o il sea l Figs. 5 and 6 are perspective views of the `retaining members for the seal of Fig. 4.

Referring to the drawing the numeral 2 indicates the differential carrier of an automotive vehicle. Tin the housing there is enclosed the driven axle comprising the two halves 4 and 6. Each ax'le 'half has secured to its ends the bevel gears 8 and 10 which mesh with the pinions 12 of the differential. The differential is of the usual type and comprises the worm gear 14 and the difierential pinion case 16. The carrier is provided at its outer portion with the splines 18 which mesh with and correspond to the as splines 20 of the' ring gear 14.

By referring to Fig. 1 it will b'e noted that at intervals as shown at 22 the splines of the case 16 as well as on the ring gear 14 are interrupted. At each of these interbearing opening 24 is rupted portions a provided and in each opening there is mounted one stud 26 of a s der 28. On each stud 26 one of the di mounted. I915 In lprior constructions the splines 18 and.

2O have extended around the entire periphery of the pinion carrier which necessitated a much larger case. The structure of the present invention enables a small worm erential pinions 12 .is

' extensions 30,

` At-the lower portion of the axle housing '2, the usual rear and front bearing seats 34 and'36 are provided. AAt the rear bearing seat 34 the usual radial bearing 38 is provided while at the front a thrust bearing 40 isl positioned. In the present practice ythe position of the bearings 38 and 40 is usually reversed; that is, the thrust bearing 40 is at therear while the radial bearing 38 is at the front. As will be seen from Fig. 1,` the worm 42.h as a shoulder 43 abutting thebearing 4G and is inclined to the horizontal to correspond to the inclination of the propeller shaft, the universal joint iange of which is'indicated at 44. With the bearing 40 at the rear in place of the bearing 38 it will be apparent that a much lesser ground clearance will be allowed for the reason that the. bearing 4Q is much larger andfwould therefore extend further to the rear and a reductionin gear diameter brou ht about lation, at one end to the ring 54 and at' its by the interrupted splines 22 on t e pinion carrier 16. j

:The differential carrier 2 is provided with' an opening at its front end to allow for the insertion of the worm 42. In this' opening the bearing 40 (which 'may be either. ball or roller) is mounted which bearing is held in position by means of the retaining member 46 preferably secured by means of bolts ential carrier 2.

AA washer 48 -is rigidly mounted on the shaft portion 50 of the worm `42 and has its outer portion formed with a spherical seat as indicated. at 52. A sealing ring 54 fits over the washer 48 and isprovided lwith a spherical seat 56 which conforms to the vspherical seat 52 on the washer 48. -The center of the sphere defined by the surfaces 52 and 56 is positioned aty 58 which is the center of zero bending,'or at approximately, the center of the bearing 40.

A bellows 58 is secured in oil tight r opposite end tothe retainer 46. Ow' the exibilityA of the bellows the ring 54v will be urged constantly against the washer 48 to maintain the spherical surfaces 52 and 56 tightly in contact and. at all times to form a tight orleak proof oil joint or seal. .ln additonthe helical compression spring (not shown) to the diierl' the sleeve 76 of the universal joint.

(The. retainer l is secured to the axle ing, any movement of the shaft 50 about the zero bending center will also shift the spherical surfaces relatively to each other to thereby insure a tight seal at all times in' spite of distortion of the parts.

The bellows 58 also prevents the escape of oil from the bearing. By referring to Fig. 1. it will be noted that a slight clearance is allowedV between the ring 54 andthe interior of the retaining member 46. This will allow oil to escape to the space between the bellows and the retainer 46 but no oil will be permitted to escape because ofthe tightness of the contact of the bellows with 'the ring and retainer. A spring 59 is also 1, a tapered roller bearing 40 is use Either form of bearing' will work just as well. The washer 48 is the same as that shown in Fig. 1 while the ring 54 is slight- .ly modified. Around the ring 54 there is seated the washer 60 having the flanged to Fig. s, it will be seen `that instead o the ball bearing 40 of Fi edge 62. -The flange l62l is4 in liquid tight relation with the interior of the retainer v washer 60 and ring 54 toward the washer v48 to maintain the spherical 'surfaces in contact at all times to oilI seal. i

Referring to Figs. 4, 5 and 6, it will be seen that a dil'erent'ty e of oil seal is provided. The bearing 40 is the same as that shown' in Fi 3.

At the en of the axle housing 2 a retainer 70 is provided. This retainer has the annular. inner portion 72 which presses glain'st and holds the bearing 40 in place. l

e. retainer 70 hasthe inwardly extending thereby form a tight annularportion 74 which ts closely (actul ally about 0025 to O04 clearance radially) 'about the sleeve portion 76 ofthe universal joint flange 44. A packing 78 is seatedwithin the hollow 77 of the retainer 70 and over this. packing there .is received vthe collarv the packing into liquid tight vrelation housing 2 'by means of bolts'- passing portion 79 of the gland 8O to rmly force .with

through the Openings indicated at 82 in Y u Fig. 6. The vgland/ 80 is secured to the relas' tainer 70d (and also to theaxlehousing` if desired) lby means of the bolts-passing` through openings 84 inears 86 formed at one side of the' gland. 'The retainer 70 is' provided with, lateralv openings` 88 (which,

iso

conform with the openings 84) and are adapted -to accommodate the bolts which secure the gland 8O to the retainer 70 and housing 2.

I claim:

1. In a differential, a ring gear surroundin said differential, a pinion case inside said gear, meshing splines on said gear and case, conforming interrupted portions on said splined portions, a di'erential pinion spider having a plurality of arms, said arms mounted in openings formed at said interrupted portions of said case, and pinions mounted on said arms.

2. In a differential, an outer ring gear,

an inneripinion case ri idly connected with said gear by means o interittin sectors, mating plain portions intermediate said sectors, and a pinion carrier mounted at said plain ortions.

3. In a ''erentiah an outer` ring gear, aninner pinionoase ri dly connected with said'gearbymeans o interfittn sectors,

mating plain portions intermediate saidv sectors,- a pinion carrier, -and armson said carrier mounted at said plam portions, the ends of said arms extendin past the inner 'circumference of said inter tting sectors.

In testimony whereof I aiix my signature.

ROLAND V. HUTCHINSON. 

